Exhaust gas heat exchangers of the generic type are well known and, to produce a sealed connection, are usually soldered in a soldering furnace and/or welded in a welding process. In order to be able to fix the individual components that are to be soldered or welded together relative to one another during the soldering process or welding process, what are referred to as soldering frames or soldering stands or corresponding welding stands or welding frames are usually used.
DE 10 2008 019 320 A1 discloses an exhaust gas heat exchanger having a heat exchanger block with a first axial termination device and with a second axial termination device, in which the heat exchanger block has both axial inlet openings and axial outlet openings and in which means for forming a form fit with the axial termination device are arranged on the heat exchanger block. The means for forming the form fit in that case protrude axially at least in part beyond the axial inlet openings and/or beyond the axial outlet openings of the heat exchanger block such that they are able to be arranged radially next to bearing shoulders of the axial termination devices, with the result that a particularly radially pressure-tight heat exchanger can be provided.
WO 2012/019912 A1 discloses a method for producing an exhaust gas heat exchanger for a motor vehicle, in which a tube bundle that receives exhaust gas of the motor vehicle is fastened in a prefabricated housing and is subsequently soldered to the housing. In order in that case to be able to dispense with an expensive soldering stand, the housing is elastically deformed by an extensively acting force, wherein the tube bundle is introduced into the housing while the force is being applied and, after the tube bundle has been positioned in the housing, the latter is relieved of the force, with the result that the tube bundle is braced inside the housing.
As already mentioned above, in order to solder/weld an exhaust gas heat exchanger, what are referred to as soldering stands/soldering frames or welding stands/welding frames have previously been used, but these require not inconsiderable assembly effort and cleaning effort. Furthermore, the assembly also increases the cycle time, with the result that the production costs of such an exhaust gas heat exchanger are increased.